title: [Tissue polypeptide antigen liberation and proliferation of MCF-7 cells after synchronization with hydroxytamoxifen and rescue with estradiol].
abstract: The kinetic of release of the tissular polypeptide antigen (TPA) by MCF-7 cells synchronised by sequential treatment with hydroxytamoxifen (OH-TAM) and 17 beta-estradiol has been studied. The present findings confirm the proliferative effect of estradiol on MCF-7 cells, with a shortening of the doubling time (TD) (22.2 h versus 24.8 h) and an increase in the growing fraction (Fc) (94% versus 81%) when compared with the same parameters measured in cells rescued from OH-TAM but not treated with estradiol. In addition, the action of estradiol was followed by a simultaneous increase in the amount of TPA in the culture medium related with the phases G2/M and G1 of the mitotic cycle. This phenomenon seems to be the reason for the steplike shape of the TPA released curves. The experimental results suggest that in MCF-7 cells the sequential combination of antiestrogenic agents and estrogens leads to a cellular synchronization. Furthermore this synchronization is maintained for at least 3 cycles of cell division.
authors.affiliation: Departamento de Radiología, Hospital Clínico Universitario, Facultad de Medicina, Universidad de Granada, España.
authors.forename: J M
authors.initials: JM
authors.lastname: Ruiz de Almodóvar
authors.forename: J D
authors.initials: JD
authors.lastname: López-González
authors.forename: R
authors.initials: R
authors.lastname: del Moral
authors.forename: J C
authors.initials: JC
authors.lastname: Fernández
authors.forename: L
authors.initials: L
authors.lastname: Gorgojo
authors.forename: N
authors.initials: N
authors.lastname: Olea
authors.forename: V
authors.initials: V
authors.lastname: Pedraza
mesh_terms: D000941:Antigens / Q000378:metabolism*; D002455:Cell Division / Q000187:drug effects*; D004958:Estradiol / Q000494:pharmacology*; D006801:Humans; D008938:Mitosis / Q000187:drug effects; D010455:Peptides / Q000378:metabolism*; D013629:Tamoxifen / Q000031:analogs & derivatives* / Q000494:pharmacology*; D019396:Tissue Polypeptide Antigen; D014407:Tumor Cells, Cultured / Q000276:immunology*
chemical_list: D000941:Antigens; D010455:Peptides; D019396:Tissue Polypeptide Antigen; D013629:Tamoxifen; D004958:Estradiol
vernacular_title: Liberación de antígeno polipeptídico tisular y proliferación de células MCF-7 tras sincronización con hidroxitamoxifeno y rescate con estradiol.